5motor control (mctrl) – Lenze 8400 TopLine User Manual
Page 277
Lenze · 8400 TopLine · Reference manual · DMS 6.0 EN · 06/2014 · TD05/TD14
277
5
Motor control (MCTRL)
5.10
Parameterisable additional functions
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[5-27] Speed/torque characteristics of a synchronous servo motor with field weakening
Short overview of the relevant parameters:
• The maximally effective field-producing motor current is calculated based on the motor data
and
. Then, the value is internally limited to 98 % of the set
maximum current (
or maximally permissible current for the permanent switching
frequency set in
•
serves to limit the maximally effective field-producing motor current as well.
• In the Lenze setting, the field weakening for synchronous motors is active (
However, the field-producing motor current is limited via
to 30 % of the rated motor
current (
). Hence, the maximum speed is limited during field weakening operation
and, at the same time, the temperature rise of the motor during field weakening operation
and no-load operation is also limited.
• If a higher speed for the field weakening operation is required or the current in the field
weakening operation is to be limited (e.g. since no motor temperature detection is available
and/or heating in the field weakening operation is to be limited), the value must be increased
or reduced accordingly in
Standstill torque
Rated torque
Characteristic for continuous operation
Limit characteristic at a mains voltage of 400 V without field weakening
Limit characteristic with field weakening
0
10
20
30
40
50
60
M [Nm]
0
1500
3000
4500
0
1
n [rpm]
Parameter
Info
Lenze setting
Value Unit
Field weakening
1: On
Limitation of maximally effective field-producing
motor current
• With regard to rated motor current (
30 %
Maximally effective field-producing motor current
- A
Highlighted in grey = display parameter